The newest 9 of 8 written questions. Open one to see it on the real paper.
Complete Table 5.1 to match the time taken for each reaction to finish with the reaction number. Table 5.1 time taken for reaction to finish/s 200 100 50 reaction number
See it on the paper →Suggest how long it will take for the X to disappear. time disAPPear
See it on the paper →The reaction gets faster as the temperature increases. Explain how you can tell this from Table 8.1.
See it on the paper →Tick (3) two reasons in Table 8.2 which explain why reactions get faster as the temperature increases. Table 8.2 reason tick (3) particles are closer together particles collide more often particles have less energy particles have a larger surface area particles move faster
See it on the paper →The student repeats the experiment. He uses the same volume of hydrochloric acid and the same mass of magnesium. This time he increases the temperature of the hydrochloric acid. All of the magnesium reacts with the acid. On Fig. 8.3, sketch the shape of the graph you would expect this time.
See it on the paper →State what happens to the rate of the reaction between 1 and 4 minutes.
See it on the paper →It takes 50 seconds for 80 cm 3 of gas to collect in the gas syringe. Calculate the rate at which the gas is produced in cm 3 / s. rate = cm 3 / s
See it on the paper →The teacher repeats the experiment, adding dilute hydrochloric acid at 30 °C to excess calcium carbonate powder. Sketch the graph she obtains on Fig. 5.2.
See it on the paper →State the volume of gas produced in 10 minutes when dilute hydrochloric acid at 20 °C is added to excess calcium carbonate powder. dm 3
See it on the paper →Most candidate correctly stated the relationship between temperature and time. A few just quoted data without describing the relationship.
— Examiner report, May/June 2023, 0654/41 Q8(b)(i) (Cambridge)
Almost all candidate correctly identified why reactions get faster when the temperature increases.
— Examiner report, May/June 2023, 0654/41 Q8(b)(ii) (Cambridge)
The increased initial rate of reaction at higher temperature was often correctly shown by a steeper line on the graph. A minority of candidates showed that the yield is unchanged by drawing a line which levelled off at the same volume as before.
— Examiner report, May/June 2022, 0654/43 Q8(c)(iii) (Cambridge)
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